the sea

• What causes waves to stack up?

  Friction
• Constructive waves causes?

  deposition
• destructive waves causes?

  erosion
• Describe constructive waves?

  - swash is greater than backwash/ brings material onto coast

  -less than 10 waves per min
• Describe destructive waves?

  -backwash is greater than swash/ brings material away from coast

  - more than 10 waves per min
• What is swash?

  waves that wash up onto the beach
• What is backwash?

  The movement of water down the beach
• Overview of waves?


  Waves erode, transport and deposit material along the coast.

  Waves are formed by wind moving across the surface of the sea.

  The distance of open sea over which the wind blows is called the fetch.

  When a wave breaks, the water that rushes onto the beach is called swash.

  The water that returns back down the beach is known as backwash.
• Processes of costal erosion?

  Hydraulic action,

  abrasion,

  compression,

  solution,

  attrition
• Explain hydraulic action?

  The physical force of waves breaks material off the coastline.
• Explain abrasion

  Loose material, [rocks and sand] is thrown against the coastline by the waves.
• Explain compression?

  when waves crash against a cliff, air gets trapped in the cracks and joints on the cliff face and becomes compressed.
• Explain solution?

  some rocks, such as limestone and chalk are dissolved by water
• Explain attrition?

  Stones that are carried in the water are constantly hitting against each other
• name features of costal erosion?

  -sea arch

  -sea cave

  -sea stack

  -sea cliff

  -sea stumps

  -wave cut platforms

  -blow hole

  -bays + headlines.
• Diagram of a sea cliff?

  
• Explain sea cliff?

  A sea cliff is a vertical or steep slope on the coastline.

  Waves erode a notch at a line of weakness, this notch grows longer due to the hydraulic action of the waves.

  Cutting of the waves then occurs.

  Overhang eventually collapses

  the sea erodes further and the rock it erodes gets higher, a cliff is formed.

  Compression and abrasion constantly erodes the cliff so that it retreats into the coastline.

  The rock that is left at the base of the cliff is called a wave- cut platform.
• Example of sea cliff?

  Cliffs of Moher, Co. Clare
• define bays and headlands?

  A bay is a curve where the waves have eroded the coastline.

  A headland is an area of hard rock jutting into the sea.
• examples of bays and headlands?

  bay; Dublin Bay

  headland; Bray head
• Define sea caves?


  a sea cave is a tunnel at the base of a cliff.
• example of a sea cave?


  Ballybunion, Co. Kerry
• define sea arch?


  a sea arch is an arched shaped tunnel htat stretches through a headland.
• example of sea arch?

  bridges of Ross, Loop Head, Co Clare.
• define sea stack and stump?

  a sea stack is a pillar of rock cut off from the cliff or headland an is left standing on its own.

  over time, the sea stack id eroded and it collapses. A sea stump is formed.
• Example of a sea stack and stump


  Cnonc Na Mara, Co Donegal
• define blow hole?


  a blow hole is a passage that links the surface of the cliff top with the roof of a sea cave.
• example of blow hole?

  Two pistols and McSwynes gun, Co Donegal.
• Features of costal deposition?

  beach

  sand bar

  sand spit

  lagoon

  tambolos

  sand dune
• define beaches

  a build up of sand and shingle that has been deposited by constructive waves.
• explain the formation of beaches? [ costal deposition]

  swash carries material up the shore and then deposits it.

  the heaviest material is dropped first.

  the finer material is brought up the shoreline.

  this builds to form a beach.

  during a storm, waves are stronger and are able to carry heavier material.
• define sandspit?

  A sandspit is a long ridge of sand or shingle that stretches across a bay and is connected to one side of the bay.
• define lagoon?

  a lagoon is an area of sea that has been cut off by a sand bar.
• define tambolo?

  a tambolo is a ridge of sand that connects the mainland to an island.;
• define sandbar?

  sandbar is material connecting two headlands together.
• diagram of beach

  check if right.
• explain longshore drift?

  -longshore drift brings material to shoreline.

  -process of transportation

  -swash brings material at an angle, matching the direction of the wind.

  -creates a zig-zag pattern on the coastline.

  - creates features of costal deposition, ex; beaches
• define sand dune?

  - a build up of sand at the back of the shoreline.

  - contains marram grass, which is planted to keep sand dunes in place.

  - has deep roots which anchors the grass into the sand.
• explain costal protection?

  methods have been put into place to prevent Erosion or encourage deposition
• name the methods of costal protection?

  - sea walls

  - rock armour

  - groynes

  - Gabions